Michael Jackson appeared "a little loopy" after visits with his longtime dermatologist, a choreographer who worked one-on-one with the pop superstar told a jury Tuesday.

Travis Payne said he witnessed Jackson's unusual behavior after the singer visited Dr. Arnold Klein, who Payne believed was performing cosmetic treatments on the singer so that he would be comfortable performing onstage again.

"Sometimes in rehearsal, Michael would appear just a little loopy," Payne said, adding that the singer appeared to be "assisted or under the influence of something."

Under cross examination, Payne acknowledged that much of Jackson's behavior, including grogginess, lethargy, insomnia and occasional paranoia, were possible symptoms of prescription drug abuse. He also had to admit that he could not recall all the times he and Jackson rehearsed one-on-one, despite telling jurors Monday that he and the singer worked out daily.

Payne was working for AEG Live LLC, the company promoting Jackson's the This Is It tour, which was canceled after Jackson's June 2009 death.

He said he relayed his concerns about Jackson's possible prescription drug use to tour director Kenny Ortega.

The choreographer is testifying for AEG, which is being sued by Jackson's mother. Katherine Jackson claims AEG failed to properly investigate Conrad Murray, the doctor who was convicted of involuntary manslaughter for Jackson's death, and that the concert promoter also missed or ignored signs of Jackson's poor health.

AEG denies it hired Murray and claims Jackson was private about medical treatments and hid the depths of his prescription drug addiction. Jackson died from an overdose of the anesthetic propofol, which Murray was giving him as a sleep aid.

The company also did not hire the dermatologist, Klein.

Klein is listed as a potential witness in the case, but it's unknown whether he will testify. His treatment of Jackson, which included Demerol shots, have been scrutinized both during Murray's 2011 criminal trial and the current civil case.

Payne, the choreographer, said he witnessed Jackson's unusual behavior several times in the weeks before his death. The singer also appeared groggy during some morning sessions, Payne said, and Jackson occasionally complained he was having trouble sleeping.

Payne initially said under questioning by AEG attorney Jessica Stebbins Bina that he did not think Jackson had a problem with prescription medications. However, under questioning by Katherine Jackson's attorney Brian Panish, Payne said he was concerned about Jackson's medication use.

"At the moment, I had no inkling of what was ultimately revealed after Mr. Jackson's passing," he said.

He told the jury he thought Jackson was thin but he wasn't aware of an email that AEG executives sent seeking to remove footage of Jackson rehearsing in the This Is It film in which he was described as looking like "skeletal." The email was not displayed for the jury.

Payne and Panish engaged in several testy exchanges during cross-examination, including about whether Jackson was always present at his one-on-one rehearsal sessions at the singer's home. Payne acknowledged Jackson sometimes skipped sessions.

"I don't have a dog in this race," Payne said at one point. "I'm just trying to have a conversation with you and tell the truth."

Payne told jurors he met Murray twice, but both encounters were brief.

He worked with Jackson beginning in the 1990s and testified that he never saw Jackson drink alcohol or take any medications. The singer also never discussed his medical treatments, Payne said.